#define _CRT_SECURE_NO_WARNINGS 1
struct ListNode* getKthFromEnd(struct ListNode* head, int k) {
    struct ListNode* fast = head, * slow = head;
    while (k--)
    {
        fast = fast->next;
    }
    while (fast)
    {
        slow = slow->next;
        fast = fast->next;
    }
    return slow;
}